[6][7] Montgomery disliked school, being expelled from six private academies before finally dropping out at the age of 15 to pursue stage acting[8] and to travel around Bali with her then-boyfriend.

[5] Montgomery emigrated to the United States at the age of 18, arriving in Florida to meet a boyfriend whom she had met when he was an exchange student.

[8] When Montgomery moved to Los Angeles, she stayed with two of her brother's friends,[9] while sending a head shot every day to Julia Roberts' former manager, Bob McGowan, until he signed her.

[10] Montgomery's big break was winning the role of Marilyn Monroe in the 2001 CBS miniseries Blonde, based on a Joyce Carol Oates novel.

[7] In 2011, Montgomery portrayed Harry Potter author J. K. Rowling in the television biographical film Magic Beyond Words.

[12] The same year, she began starring in the CBS police drama Unforgettable as Carrie Wells, a former homicide detective who is convinced to join the NYPD in Queens by her ex-boyfriend Al Burns (potrayed by Dylan Walsh) after she leaves Syracuse because the investigation into her sister's murder was shut down.

[19] In late 2011, Montgomery began dating Shawn Sanford, director of lifestyle marketing for Microsoft, whom she met in Puerto Rico.

with Kelly and Michael, Montgomery revealed that on Chinese New Year, she and Sanford were married at Disneyland in a ceremony with their children present.